How to Evaluate Scala Developer Skills

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Finding the right Scala developer can be tricky. Searching through tons of candidate and recruiter CV’s will not necessarily make it easier to distinguish between the candidates up to the job and those who just won’t fit. To help you in the search, this article will explain how to go about finding the ideal Scala developer.

Know your Scala

A general-purpose programming language, Scala (/ˈskɑːlɑː/ skah-lah) supports both functional programming and a strong static type system. A Mr. Martin Odersky at The École Polytechnique Fédérale de Lausanne (EPFL) launched the design of Scala in 2001, continuing their work on Funnel, which combined ideas from functional programming and Petri nets. Prior to Scala, Odersky worked on Generic Java, and Sun’s Java compiler tool, javac.

Scala’s main purpose is within backend development in highly co-existing applications.

The main advantages of Scala:

Objects are unchanging “by default” (e.g. all collections)
This means less risk of errors in the language, with regards to threads in particular.

An advanced type system
Since there are more types, this allows Scala to carry out a wider variety of tasks compared to more elementary languages possessing simpler type systems, Java for example.

Functional, object-focussed, and imperative programming made possible
Each task needs a different way of programming. Scala is compatible with at least three. The Scala environment, therefore, avoids the developer having to work with different environments.

What you need to know about Scala

Before using Scala, all technical recruiters need to grasp when recruiting for a Scala developer position.

  1. Scala is, at present, the leading functional programming language.  Of all its applications, the most widely used is Big Data.
  2. Scala is compatible with Java since it runs on the Java virtual machine, just like Java. In other words, Scala libraries are ok for Java applications and Java libraries ok for Scala applications. This allows them into the vast Java ecosystem, a big plus for developers using  Scala compared to other developers.
  3. However, one downside to Scala is that, unlike Java or C#, it possesses more difficult, making it harder to master Scala and subsequently harder to recruit qualified Scala developers.

Be conscious when recruiting for Scala developers, you will need to aim for an elite set of candidates, who will have chosen to master the obstacles that the Scala language presents them with.

Check skills in Scala during candidate screening

Technical screening of Scala skills based on the candidate’s resume

Identifying your candidates’ interest in functional programming is essential prior to any technical screening. By this, we mean their level of interest in mastering new languages and functional languages, for example, Haskell, F sharp, and OCaml.

The relationship between the various versions of Scala technology:

Version2.12 is the most widely used with a smaller number of developers using version 2.11. 2020 should see the release of Version 3. These main Scala versions aren’t however binary compatible – It will be necessary to recompile all libraries since the main versions are not binary-compatible whereas the smaller 2.11.1, 2.11.2, etc. are.

Assessing a Scala developer’s skills using a Scala certification.

Plenty of courses are on offer, the most popular being those from Lightbend which also give out certificates. However Scala Center has its own widely used Coursera Scala track course.

Certificates alone do not suffice as many other factors need to be taken into consideration when deciding if a candidate will be your ideal Scala developer.